Machine for forming sheet-metal pipes



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F. W. DAVIDSON.

- MACHINE FOR FORMING SHEET METAL PIPES.

Patented Mar. 26, 1889.

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F. W. DAVIDSON. MAGHINE FOR FORMING SHEET METAL PIPES. No. 400,310.

Patented Mar. 26, 1889.

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Patented Mar. 26, 1889.

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FREDRICK \V. DAVIDSON, OF PHILADELPHIA, PENNSYLVANIA.

MACHINE FOR FORMING SHEET-METAL PIPES SPECIFICATION forming part of Letters Patent No. 400,310, dated March 26, 1889.

v A li ation filed July 5, 1888. Serial No. 279,066. (No model.)

To coZZ whom it may concern.-

Be it known that I, FREDRICK W. DAVID- SON, acitizen of the United States, and a resident of Philadelphia, Pennsylvania, have invented certain Improvements in Machines for Forming Sheet-Metal Pipes or Tubes, of which the following is a specification.

The object of my invention is to provide a simple and effective machine for making rectangular pipes or tubes, preferably such as have rounded corners; and this obj ect-I attain in the manner hereinafter set forth, reference being had to the accompanying drawings, in which Figure 1 represents the end part of a rectangular sheet-metal pipe or tube, such as pro duced by the machine. Figs. 2, 3, 4, and 5 are diagrams illustrating the successive steps in the formation of a rectangular pipe or tube in the machine. Fig. 6 is a plan view of the complete machine. Fig. 7 is a transverse section of the same on the line 1 2, Fig. 6. Fig. 8 is a detached perspective view of parts of the machine; and Fig. 9 is a transverse section of the machine on the line 3 4:, Fig. 6.

The machine is intended mainly for the manufacture of a sheet-metal pipe or tube such as shown in Fig. 1, said tube being of rectangular cross-section and having rounded corners, a longitudinal seam, a, on one of its sides, and one end crimped at the corners, as shown at b, so that this end of the pipe may be readily adapted to the end of an adjoining section of pipe in fitting successive lengths'of pipe together. The main elements of the machine for forming said pipe are the presserbar A, opposite side dies, 13 B, supplementary side dies, D D, and opposite gages F F, the operation of forming the pipe being illustrated in the diagrams, Figs. 2, 3, a, and 5, on reference to which it will be seen that the first step in the operation is to insert one edge of the thin metal sheet from which the pipe is removed and readjusted between said bar and the side dies, as shown in Fig. 4, the opposite edge of the sheet now bearing against the opposite side gage, F, to determine the proper position of the sheet in respect to the presserbar and dies. When the presser-bar is again depressed, as shown in Fig. 5, there is a further bending of the sheet which is now reduced to the form of the desired rectangular tube, the edges of the sheet overlapping at one side of the tube, so that they maybe soldered together or otherwise joined in any desired manner.

In order to provide for the manufacture of tubes of various sizes, the presser-bar A has adjustable side strips, cl, which are carried by slotted wings d on the presser-bar, as shown in Fig. 6, so that they may be adjusted from and toward the center of said presser-loar and the width of the latter thus varied as desired. For the same reason the gages F are carried by slotted wings e on the side bars, B, of the machine, and said side. dies, B, have nuts f. adapted to screw-stems g, confined longitudinally to but free to turn in the side flanges of the table G, so that by turning these screwstems the side dies may be moved from and toward each other, to accord with the expansion or contraction of the presser-bar A. The supplementary side pressers, D, are mounted upon and are free to move independently of the side dies, B, but are confined vertically thereto by pins w, adapted to slots in the pressers D, as shown in Fig. 6, and each of these supplementary pressers is acted upon by cams J, connected together bya rod, h, one of the cams having an operating-handle, i, by swinging which, in one direction or the other, the supplementary pressers D may be caused to move in or out on the side dies.

The presser-bar A is carried by rods m, which are connected to a bar, m, and the latter is acted upon by a treadle-frame, K, and by a spring, M, the tendency of which is to lift the bar m and thus maintain the presserbar A always in the elevated position, except when it is depressed by the action of the treadle-frame. One end of the presser-barA has ribs or corrugations k, as shown in Figs. 8 and 9, and each of the side dies, B, has at one end a ribbed and grooved projection, n, the grooves of the projection corresponding with the ribs of the presser-l.)ar, so that when said presser-bar is brought down to bend the sheet-metal strip between the side dies a portion of said strip will be pressed into the grooves of the projections n and will thereby be corrugated. Each of the supplementary side pressers, D, also has a ribbed or corrugated portion, 1), at one end, and when the presser-bar A has been brought down these supplementary side pressers are acted upon by the cams J, so as to bring them together and cause their ribbed or corrugated. ends to act in conjunction with the ribbed end of the presser-bar to eiieet the crimping or corrugating of the sides of the tube at and near the bonds, as shown in. Fig. 1.

It will be evident that by a proper formation of the presser-bar and dies of the machine sharp-cornered pipes can be formed therein, as well as round-cornered pipes.

Having thus described my invention, I claim and desire to secure by Letters Patent 1. The combination, in a machine for forming rectangular sheet-metal pipes or tubes, of the presser-bar consisting of a fixed central portion having projecting wings, and independent side strips, adjustable laterally on said wings, the opposite side dies, means for adjusting the latter, and the opposite gages for the strip to be bent, substantially as specified.

2. The co1nbination,in a machine for forming rectangular sheet-metal pipes or tubes, of the presser-bar having adjustable side strips,

the opposite side dies having laterally-pro- 1 jecting wings, the opposite gages carried by said wings, and means for laterally adjusting the presser-bar strips, side dies, and gages to suit the different sizes of pipe to be manufactured, substantially as specified.

3. The combination of the presser-bar having a ribbed end with the side dies having ribbed projections forming counterparts of the ribbed end of the presser-bar to effect the crimping of the end of the pipe, all substantially as specified.

4. The combination of the prcsser-barl1aving a ribbed end with the side pressers laterally movable and also ribbed at one end, all substantially as specified.

5. The combination of the presser-bar having a ribbed end, the side dies having ribbed projections at one end, and the supplementary side pressers also ribbed at one end, all sub stantially as specified.

6. The combination of the presser bar ribbed at the ends, the side dies having ribbed projections at the ends, the supplemei'ltary side pressers mounted on the side dies and also ribbed at the ends, and the connected cams for operating said side pressers, substantially as specified.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

FREDRIOK \V. DAVIDSOY.

\Vitnesses:

\VILLIAM D. OoNNER, HARRY SMITH. 

